A simple way to obtain substantial savings:

The Galley Demand Controlled Ventilation system (GDCVs) system is making savings simple by reusing the existing equipment, but controlled differently. GDCVs consider the entire saving potential in both hood, canopies and galley with variable air volume (VAV) and variable cooling.

Functionality
GDCVs can identify the load on the cooking device and the galley activity. Existing hood/canopy dampers will close when the cooking equipment is not in use, and the exhaust air reduced and the supply air reduced to keep a slight under pressure to surrounding areas.

Modification of the system from constant air volume and supply air control to room VAV, temperature, humidity control, to increase the well-being and saving.

Process:
The first step is a survey and saving analyze.

Next step is to install needed equipment, which is Hood/Canopy IR sensors – current meters – solenoid valve signal, Damper aux. relay, room temperature, humidity and differential pressure sensors, the new interface control cabinet and serial cable to existing HVAC Control system and modify the software. VFD’s for fans and a cooling valve if not already installed.

Last step is to test and commissioning the system to feel the improved comfort and save at the same time.

Hood Principle:

The sensors constant measure the activity in the Galley, and define the status as Cooking, Stand-By (Heating up/down) and Off.

The airflow through the Hood (Dirty exhaust ducts), will be will be reduced by closing the existing Hood dampers.

The cooking activity detected by either measurement of current consumption or an IR sensor.

The total airflow will then be constantly calculated, when dampers are closing, and the exhaust fan speed reduced accordingly.

Canopy Principle:

The principle for a Canopy is the same as for a Hood.

If the clean exhaust duct does not have a damper, installation of those is required.

Detection of cooking activity either by measurement of current consumption or detection on the solenoid valve.

General Galley Ventilation and temperature regulation

The pressure to the surrounding areas and the temperature in the galley area control the general ventilation. The supply and general exhaust fan will regulate up and down and keep a small under pressure to the surrounding areas when the hood/canopy fan is opening/closing.

Galley temperature will control the supply fan and cooling coil. A humidity sensor controls the cooling valve for dehumidification.

Automated System:

For the daily operation, no human interaction is necessary, as the system is a fully automated. However, adjustment of temperature setpoints and fan speed is possible from a user interface. The user interface can be either the existing HVAC HMI in ECR or a stand-alone user touch panel located in either ECR or in the Galley.

In the Galley, a new controller must be installed, connecting all the equipment and interfaces to existing HVAC control system.

All existing operation, start/stop of fans, hood wash, ESD closing etc. will not be modified only fan speed reference and regulation sequence to be changed in the HVAC Control system, to improve the saving.

Saving:

The energy saving is calculated to be 35-40% for the fan and the cooling energy. The combination of closing hoods not used, and variable air volume in the galley, will improve the saving significant. Adding temperature control of both supply/exhaust fan speed and chilled water flow will even increase the saving, as well as free cooling in colder climate. The simultaneous factor combining above principle, will generate a higher saving in both tropical and colder climate zones and improve the ROI.

For a Main Galley, consuming 3.600-3.800 MW/Yr the annual saving is app.
USD 155.000,00 and ROI < 11 Month - A simple way to obtain substantial savings.